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使用phpspreadsheet给单元格设置下拉选项的时候，如果文件类型是xlsx，那么下拉项里面可以有中文。

use app\BaseController;
use PhpOffice\PhpSpreadsheet\Cell\DataValidation;
use PhpOffice\PhpSpreadsheet\Spreadsheet;
use PhpOffice\PhpSpreadsheet\Writer\Xlsx;
use think\response\Json;
use utils\CacheUtils;

class Test extends BaseController
{
    public function test()
    {
        // 创建Spreadsheet对象
        $spreadsheet = new Spreadsheet();
        $sheet = $spreadsheet->getActiveSheet();

        // 为A1单元格添加下拉选项
        $validation = $sheet->getCell('A1')->getDataValidation();
        $validation->setType(DataValidation::TYPE_LIST);
        $validation->setErrorStyle(DataValidation::STYLE_INFORMATION);
        $validation->setAllowBlank(false);
        $validation->setShowDropDown(true);
        $validation->setFormula1('"开启,关闭"'); // 下拉选项值

        // 直接输出Excel文件到浏览器
        $writer = new Xlsx($spreadsheet);

        // 设置响应头,xlsx文件类型
        header('Content-Type: application/vnd.openxmlformats-officedocument.spreadsheetml.sheet');
        header('Content-Disposition: attachment;filename="1111.xlsx"');
        header('Cache-Control: max-age=0');


        $writer->save('php://output');
        exit;
    }
}

如果文件类型是xls，那么下拉项里面不可以有中文。下面代码将会报错。

use app\BaseController;
use PhpOffice\PhpSpreadsheet\Cell\DataValidation;
use PhpOffice\PhpSpreadsheet\Spreadsheet;
use PhpOffice\PhpSpreadsheet\Writer\Xls;//！！！引入
use PhpOffice\PhpSpreadsheet\Writer\Xlsx;
use think\response\Json;
use utils\CacheUtils;

class Test extends BaseController
{
    public function test()
    {
        // 创建Spreadsheet对象
        $spreadsheet = new Spreadsheet();
        $sheet = $spreadsheet->getActiveSheet();

        // 为A1单元格添加下拉选项
        $validation = $sheet->getCell('A1')->getDataValidation();
        $validation->setType(DataValidation::TYPE_LIST);
        $validation->setErrorStyle(DataValidation::STYLE_INFORMATION);
        $validation->setAllowBlank(false);
        $validation->setShowDropDown(true);
        $validation->setFormula1('"开启,关闭"'); // 下拉选项值

        // 直接输出Excel文件到浏览器!!!此处更改
        $writer = new Xls($spreadsheet);

        // 设置响应头！！！此处更改为xls文件类型
        header('Content-Type: application/vnd.ms-excel');
        header('Content-Disposition: attachment;filename="2222.xls"');
        header('Cache-Control: max-age=0');


        $writer->save('php://output');
        exit;
    }
}